A conventional control vehicle is disclosed in US 2006/0044161 A1. The conventional control vehicle has several antennas which are arranged on the vehicle in different directions and can be selected via an antenna switch, in order to selectively access on-board units located in a specific range around the control vehicle via an antenna directed to this range.
DE 10 2008 016 311 A1 discloses how to set an antenna characteristic or an antenna array for a C2C or C2X communication depending on information sources in the vehicle, e.g. a digital road map, a measured value, an environmental sensor or an external signal.
In road toll systems of the above-mentioned type, on-board units (OBUs) installed in vehicles are used to charge vehicles for passing toll roads, for example in the form of road, zone or time tolls. For this purpose, the OBUs may be localized by geographically distributed radio beacons, e.g. infrared, RFID, DSRC, video or mobile network beacons (base stations), the narrow communication range of which uses short-range communications to localize OBUs, or by means of satellite navigation receivers in the single OBUs which can in addition be contacted via DSRC, e.g. for control purposes.
In order to control the proper function of the OBUs installed in the vehicles during operation, control vehicles which poll the OBUs of vehicles passing in moving traffic via the DSRC radio interface are frequently used. So far, such control vehicles have mostly been used only on highways which are characterized by one-way traffic. Anew approach now provides for the control of vehicles also on lower-level roads and in two-way traffic sections. However, when polling OBUs of the oncoming traffic, the time available for a polling process may be too short at high speeds due to the speeds adding up and the limited radio range of the DSRC radio interface. The invention identifies this problem and aims at providing a solution to this end.